sim-cli/fix: re-add doc for create_simulation_with_network

This was mistakenly omitted while rebasing

Author: chuksys

sim-cli/src/parsing.rs

@@ -242,6 +242,16 @@ struct NodeMapping {
     alias_node_map: HashMap<String, NodeInfo>,
 }
 
+/// Creates a simulation that will run on an entirely-simulated network defined in `sim_params`,
+/// returning the simulation, a validated vector of any defined activities that were specified and
+/// a map of all the simulated nodes in the network. Note that if `sim_params::exclude` was set,
+/// the nodes will be excluded from the set of nodes actively sending/receiving random payments,
+/// but they will be included in the map so that they are available for use outside of the
+/// simulation.
+///
+/// This network can be customized by providing `interceptors` that will act on every HTLC that is
+/// forwarded by the network, and setting `custom_records` which will be set as the default TLV
+/// records set by the original sender of payments in their simulated `update_add_htlc`.
 pub async fn create_simulation_with_network<P: PathFinder + Clone + 'static>(
     cfg: SimulationCfg,
     sim_params: &SimParams,